<p>The role of human capital in driving urban growth has been a central topic in urban economics and economic geography. However, limited attention has been given to how skill-based human capital contributes to sustainable urban employment growth, particularly in developing countries undergoing technological transitions. This study examines the impact of skill-based human capital on employment growth using China’s 2000, 2010, and 2020 census data. Measuring skill-related thickness through skill-relatedness density, we find a significant positive effect on employment growth, primarily through creating new firms and enhancing innovation outputs. The impact varies across skill types and city sizes: cognitive and technical skills play the most prominent roles in driving employment growth by promoting both entrepreneurship and innovation, and the positive effect of skill-related thickness is stronger in large cities. This study provides policy insights on how cultivating skill-related labour markets can enhance urban resilience and support sustainable urban development trajectories.</p>